1. Field of the Invention
The present invention relates to a structure and method useful for accurately mounting at least one electronic part such as a semiconductor device or the like on a circuit substrate.
2. Description of the Prior Art
Electronic parts such as integrated circuits (LSI) and the like are incorporated into a product after they have been mounted on a given circuit substrate. On mounting, it is required to ensure that the electrodes of the electronic parts are electrically connected with the corresponding wiring pattern on the circuit substrate.
For example, if it is wanted to mount an integrated circuit (LSI) on a circuit substrate, that is, where the projecting electrodes (hereinafter called "bumps") of the LSI are to be electrically connected with wiring patterns on the circuit substrate, the prior art used an electrically conductive paste for connecting the wiring patterns with the bumps (see FIG. 1). Such a paste may be a silver paste. Referring to FIG. 1, the bumps 12 of an LSI 11 are electrically connected with wirings 14 of a circuit substrate 13 through silver pastes 16.
Since the electrically conductive paste such as silver paste or the like is thermosetting, however, it is difficult to replace any failed integrated circuit with a new integrated circuit. When it is desired to replace an integrated circuit with a new one, the entire circuit substrate must be heated up to a temperature higher than the melting temperature of the silver paste. This may damage the other integrated circuits mounted on the same circuit substrate.